Please note: This article was published more than one year ago. The facts and conclusions presented may have since changed and may no longer be accurate. And "More information" links may no longer work. Questions about personal health should always be referred to a physician or other health care professional.

FRIDAY, Sept. 19, 2014 (HealthDay News) -- Although there is mounting evidence that muscle-strength training provides key health benefits, most middle-aged and older adults in the United States don't engage in this type of exercise, according to new research.

Less than one-quarter of adults over 45 meet the muscle-strengthening recommendations set by the Department of Health and Human Services, the study found.

Strength is essential for promoting health and fitness and staying independent, researchers advised. Muscle-strengthening activities include yoga, sit-ups, push-ups, weights, elastic bands and weight machines. In many cases, people use their own body weight for resistance during strength training.

For the study, the researchers analyzed data from the 2011 U.S. Behavioral Risk Factor Surveillance System, a telephone health survey conducted by the U.S. Centers for Disease Control and Prevention. Participants answered questions about the type of physical activities they engage in and how often. They were also asked if they exercised in order to strengthen their muscles.

Of all those who answered the questions on muscle strengthening, about 24 percent said they met the government's recommendations.

Among those less likely than others to meet these guidelines were women, widows, those age 85 or older, people who were obese, and Hispanics. Participants who didn't graduate from high school were also less likely to meet U.S. strength-training recommendations.

Jesse Vezina, of Arizona State University, and his fellow researchers concluded that interventions designed to encourage people to participate in strength training should target these high-risk groups.